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Golabi M, Kazemi D, Chadeganipour AS, Fouladseresht H, Sullman MJM, Ghezelbash B, Dastgerdi AY, Eskandari N. The Role of Cobalamin in Multiple Sclerosis: An Update. Inflammation 2024:10.1007/s10753-024-02075-6. [PMID: 38902541 DOI: 10.1007/s10753-024-02075-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 05/29/2024] [Accepted: 06/03/2024] [Indexed: 06/22/2024]
Abstract
Multiple sclerosis (MS) is a neurodegenerative condition that results in axonal and permanent damage to the central nervous system, necessitating healing owing to autoimmune reactions and persistent neuroinflammation. Antioxidant and anti-inflammatory drugs are essential for the management of oxidative stress and neuroinflammation. Additionally, multivitamin supplementation, particularly vitamin B12 (cobalamin), may be beneficial for neuronal protection. Although there is no documented connection between vitamin B12 deficiency and MS, researchers have explored its potential as a metabolic cause. This review highlights the therapeutic benefits of cobalamin (Cbl) in patients with MS.
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Affiliation(s)
- Marjan Golabi
- Applied Physiology Research Center, Cardiovascular Research Institute, Department of Immunology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Danial Kazemi
- Student Research Committee, Isfahan University of Medical Science, Isfahan, Iran
| | | | - Hamed Fouladseresht
- Applied Physiology Research Center, Cardiovascular Research Institute, Department of Immunology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mark J M Sullman
- Department of Life and Health Sciences, University of Nicosia, Nicosia, Cyprus
- Department of Social Sciences, University of Nicosia, Nicosia, Cyprus
| | - Behrooz Ghezelbash
- Laboratory Hematology and Blood Banking, School of Allied Medical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Ava Yeganegi Dastgerdi
- Department of Cell and Molecular Biology, Falavarjan Branch, Islamic Azad University of Science, Isfahan, Iran
| | - Nahid Eskandari
- Applied Physiology Research Center, Cardiovascular Research Institute, Department of Immunology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
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Huang WQ, Lin Q, Tzeng CM. Leukoaraiosis: Epidemiology, Imaging, Risk Factors, and Management of Age-Related Cerebral White Matter Hyperintensities. J Stroke 2024; 26:131-163. [PMID: 38836265 PMCID: PMC11164597 DOI: 10.5853/jos.2023.02719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 01/15/2024] [Indexed: 06/06/2024] Open
Abstract
Leukoaraiosis (LA) manifests as cerebral white matter hyperintensities on T2-weighted magnetic resonance imaging scans and corresponds to white matter lesions or abnormalities in brain tissue. Clinically, it is generally detected in the early 40s and is highly prevalent globally in individuals aged >60 years. From the imaging perspective, LA can present as several heterogeneous forms, including punctate and patchy lesions in deep or subcortical white matter; lesions with periventricular caps, a pencil-thin lining, and smooth halo; as well as irregular lesions, which are not always benign. Given its potential of having deleterious effects on normal brain function and the resulting increase in public health burden, considerable effort has been focused on investigating the associations between various risk factors and LA risk, and developing its associated clinical interventions. However, study results have been inconsistent, most likely due to potential differences in study designs, neuroimaging methods, and sample sizes as well as the inherent neuroimaging heterogeneity and multi-factorial nature of LA. In this article, we provided an overview of LA and summarized the current knowledge regarding its epidemiology, neuroimaging classification, pathological characteristics, risk factors, and potential intervention strategies.
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Affiliation(s)
- Wen-Qing Huang
- Department of Central Laboratory, Shanghai Children's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qing Lin
- Department of Neurology, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
- Xiamen Clinical Research Center for Neurological Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
- Fujian Provincial Clinical Research Center for Brain Diseases, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
- The Third Clinical College, Fujian Medical University, Fuzhou, Fujian, China
| | - Chi-Meng Tzeng
- Translational Medicine Research Center, School of Pharmaceutical Sciences, Xiamen University, Xiamen, Fujian, China
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Malek N, Nihat A, Mattoscio M, Simioni V, Deeb J, Chawda S, Cifelli A, Krommyda M. A recent surge of nitrous oxide misuse around London which merits a public health warning. Postgrad Med J 2024; 100:174-178. [PMID: 38079632 DOI: 10.1093/postmj/qgad121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/02/2023] [Accepted: 11/10/2023] [Indexed: 02/20/2024]
Abstract
BACKGROUND Use of nitrous oxide (N2O) gas for recreational purposes by young people is increasingly recognized as a public health hazard in the UK. METHODS We looked at the hospital records of patients admitted over the last 4 years to a single neurological centre in Essex to determine the demographics, presentation, and management of patients presenting with symptoms of N2O toxicity from its recreational use. RESULTS Of the 17 patients (mean age = 22.9 ± 3 years) admitted between September 2018 and October 2022, 70% were admitted between January and October 2022. All patients reported limb paraesthesiae and 16/17 reported (95%) imbalance; 11/17 (65%) showed objective limb weakness. Serum B12 concentration was low in 9/17 (53%). Plasma methylmalonic acid (n = 7) and homocysteine (n = 8) levels were elevated in all patients tested. Spinal cord Magnetic Resonance Imaging (MRI) imaging was abnormal in 10/17 (59%) patients. Nerve conduction studies were abnormal in 10/13 (77%) patients, with evidence of a symmetric, length-dependent, large fibre neuropathy. CONCLUSIONS There has been a recent surge of cases with neurological complications of recreational N2O abuse in the UK, with a relatively greater rate in 2022. Greater awareness of this condition amongst clinicians and health regulators is urgently required to prevent harm from N2O misuse in young people.
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Affiliation(s)
- Naveed Malek
- Department of Neurology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Akın Nihat
- Department of Neurology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Miriam Mattoscio
- Department of Neurology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Valentina Simioni
- Department of Neurophysiology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Jacquie Deeb
- Department of Neurophysiology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Sanjiv Chawda
- Department of Neuroradiology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Alberto Cifelli
- Department of Neurology, Queen's Hospital, Romford RM7 0AG, United Kingdom
| | - Magdalini Krommyda
- Department of Neurology, Queen's Hospital, Romford RM7 0AG, United Kingdom
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4
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Horjus J, van Mourik-Banda T, Heerings MAP, Hakobjan M, De Witte W, Heersema DJ, Jansen AJ, Strijbis EMM, de Jong BA, Slettenaar AEJ, Zeinstra EMPE, Hoogervorst ELJ, Franke B, Kruijer W, Jongen PJ, Visser LJ, Poelmans G. Whole Exome Sequencing in Multi-Incident Families Identifies Novel Candidate Genes for Multiple Sclerosis. Int J Mol Sci 2022; 23:ijms231911461. [PMID: 36232761 PMCID: PMC9570223 DOI: 10.3390/ijms231911461] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/16/2022] Open
Abstract
Multiple sclerosis (MS) is a degenerative disease of the central nervous system in which auto-immunity-induced demyelination occurs. MS is thought to be caused by a complex interplay of environmental and genetic risk factors. While most genetic studies have focused on identifying common genetic variants for MS through genome-wide association studies, the objective of the present study was to identify rare genetic variants contributing to MS susceptibility. We used whole exome sequencing (WES) followed by co-segregation analyses in nine multi-incident families with two to four affected individuals. WES was performed in 31 family members with and without MS. After applying a suite of selection criteria, co-segregation analyses for a number of rare variants selected from the WES results were performed, adding 24 family members. This approach resulted in 12 exonic rare variants that showed acceptable co-segregation with MS within the nine families, implicating the genes MBP, PLK1, MECP2, MTMR7, TOX3, CPT1A, SORCS1, TRIM66, ITPR3, TTC28, CACNA1F, and PRAM1. Of these, three genes (MBP, MECP2, and CPT1A) have been previously reported as carrying MS-related rare variants. Six additional genes (MTMR7, TOX3, SORCS1, ITPR3, TTC28, and PRAM1) have also been implicated in MS through common genetic variants. The proteins encoded by all twelve genes containing rare variants interact in a molecular framework that points to biological processes involved in (de-/re-)myelination and auto-immunity. Our approach provides clues to possible molecular mechanisms underlying MS that should be studied further in cellular and/or animal models.
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Affiliation(s)
- Julia Horjus
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Tineke van Mourik-Banda
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Marco A. P. Heerings
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Marina Hakobjan
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Ward De Witte
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Dorothea J. Heersema
- Department of Neurology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands
| | - Anne J. Jansen
- Department of Neurology, Bravis Hospital, 4708 AE Bergen op Zoom, The Netherlands
| | - Eva M. M. Strijbis
- Department of Neurology, Amsterdam UMC, location VUmc, 1081 HV Amsterdam, The Netherlands
| | - Brigit A. de Jong
- Department of Neurology, MS Center Amsterdam, Amsterdam UMC, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | | | | | | | - Barbara Franke
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, 6525 GD Nijmegen, The Netherlands
- Department of Psychiatry, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Wiebe Kruijer
- Independent Life Science Consultant, 3831 CE Leusden, The Netherlands
| | - Peter J. Jongen
- MS4 Research Institute, 6522 KJ Nijmegen, The Netherlands
- Department of Community & Occupational Medicine, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, The Netherlands
| | - Leo J. Visser
- Department of Neurology, St. Elisabeth-Tweesteden Hospital, 5022 GC Tilburg, The Netherlands
- Department of Care Ethics, University of Humanistic Studies, 3512 HD Utrecht, The Netherlands
| | - Geert Poelmans
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
- Correspondence:
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ELBini-Dhouib I, Manai M, Neili NE, Marzouki S, Sahraoui G, Ben Achour W, Zouaghi S, BenAhmed M, Doghri R, Srairi-Abid N. Dual Mechanism of Action of Curcumin in Experimental Models of Multiple Sclerosis. Int J Mol Sci 2022; 23:ijms23158658. [PMID: 35955792 PMCID: PMC9369178 DOI: 10.3390/ijms23158658] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 12/16/2022] Open
Abstract
Background: Multiple sclerosis (MS) is characterized by a combination of inflammatory and demyelination processes in the spinal cord and brain. Conventional drugs generally target the autoimmune response, without any curative effect. For that reason, there is a great interest in identifying novel agents with anti-inflammatory and myelinating effects, to counter the inflammation and cell death distinctive of the disease. Methods and results: An in vitro assay showed that curcumin (Cur) at 10 µM enhanced the proliferation of C8-D1A cells and modulated the production of Th1/Th2/Th17 cytokines in the cells stimulated by LPS. Furthermore, two in vivo pathophysiological experimental models were used to assess the effect of curcumin (100 mg/kg). The cuprizone model mimics the de/re-myelination aspect in MS, and the experimental autoimmune encephalomyelitis model (EAE) reflects immune-mediated events. We found that Cur alleviated the neurological symptomatology in EAE and modulated the expression of lymphocytes CD3 and CD4 in the spinal cord. Interestingly, Cur restored motor and behavioral deficiencies, as well as myelination, in demyelinated mice, as indicated by the higher index of luxol fast blue (LFB) and the myelin basic protein (MBP) intensity in the corpus callosum. Conclusions: Curcumin is a potential therapeutic agent that can diminish the MS neuroimmune imbalance and demyelination through its anti-inflammatory and antioxidant effects.
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Affiliation(s)
- Ines ELBini-Dhouib
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
- Correspondence: or
| | - Maroua Manai
- Laboratoire de Génétique Humaine (LR99ES10), Faculté de Médecine de Tunis, Université de Tunis El Manar, Tunis 2092, Tunisia or
| | - Nour-elhouda Neili
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
| | - Soumaya Marzouki
- Laboratoire de Transmission, Contrôle et Immunobiologie des Infections (LR11IPT02), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
| | - Ghada Sahraoui
- Laboratoire de Médecine de Précision, Médecine Personnalisée et Investigation en Oncologie (LR21SP01), Service d’Anatomie Pathologique, Institut Salah Azaiez, Bab Saadoun, Tunis 1006, Tunisia
- Faculté de Médecine de Tunis, Université de Tunis El Manar, Tunis 1068, Tunisia
| | - Warda Ben Achour
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
| | - Sondes Zouaghi
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
| | - Melika BenAhmed
- Laboratoire de Transmission, Contrôle et Immunobiologie des Infections (LR11IPT02), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
- Faculté de Médecine de Tunis, Université de Tunis El Manar, Tunis 1068, Tunisia
| | - Raoudha Doghri
- Laboratoire de Médecine de Précision, Médecine Personnalisée et Investigation en Oncologie (LR21SP01), Service d’Anatomie Pathologique, Institut Salah Azaiez, Bab Saadoun, Tunis 1006, Tunisia
- Faculté de Médecine de Tunis, Université de Tunis El Manar, Tunis 1068, Tunisia
| | - Najet Srairi-Abid
- Laboratoire des Biomolécules, Venins et Applications Théranostiques (LR20IPT01), Institut Pasteur de Tunis, Université de Tunis El Manar, Tunis 1002, Tunisia
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Srour N, Khan S, Richard S. The Influence of Arginine Methylation in Immunity and Inflammation. J Inflamm Res 2022; 15:2939-2958. [PMID: 35602664 PMCID: PMC9114649 DOI: 10.2147/jir.s364190] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 05/06/2022] [Indexed: 12/24/2022] Open
Abstract
Exploration in the field of epigenetics has revealed that protein arginine methyltransferases (PRMTs) contribute to disease, and this has given way to the development of specific small molecule compounds that inhibit arginine methylation. Protein arginine methylation is known to regulate fundamental cellular processes, such as transcription; pre-mRNA splicing and other RNA processing mechanisms; signal transduction, including the anti-viral response; and cellular metabolism. PRMTs are also implicated in the regulation of physiological processes, including embryonic development, myogenesis, and the immune system. Finally, the dysregulation of PRMTs is apparent in cancer, neurodegeneration, muscular disorders, and during inflammation. Herein, we review the functions of PRMTs in immunity and inflammation. We also discuss recent progress with PRMTs regarding the modulation of gene expression related to T and B lymphocyte differentiation, germinal center dynamics, and anti-viral signaling responses, as well as the clinical relevance of using PRMT inhibitors alone or in combination with other drugs to treat cancer, immune, and inflammatory-related diseases.
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Affiliation(s)
- Nivine Srour
- Segal Cancer Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, H3T 1E2, Canada
- Gerald Bronfman Department of Oncology, and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Sarah Khan
- Segal Cancer Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, H3T 1E2, Canada
- Gerald Bronfman Department of Oncology, and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
| | - Stephane Richard
- Segal Cancer Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, H3T 1E2, Canada
- Gerald Bronfman Department of Oncology, and Departments of Biochemistry, Human Genetics, and Medicine, McGill University, Montréal, Québec, H3T 1E2, Canada
- Correspondence: Stephane Richard, Email
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Cong H, Liang M, Wang Y, Chang H, Du L, Zhang X, Yin L. Icariin ameliorates the cuprizone-induced acute brain demyelination and modulates the number of oligodendrocytes, microglia and astrocytes in the brain of C57BL/6J mice. Brain Res Bull 2021; 175:37-47. [PMID: 34274431 DOI: 10.1016/j.brainresbull.2021.07.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 06/25/2021] [Accepted: 07/13/2021] [Indexed: 12/11/2022]
Abstract
This study aimed at testing the hypothesis that treatment with icariin (ICA, a type of flavonoid) could mitigate the cuprizone (CPZ)-induced acute demyelination in the brain of mice and the potential mechanisms. Female C57BL/6J mice were fed continually with regular rodent chow or the chow supplemented with CPZ (0.2 % w/w) for six weeks to induce acute demyelination. The CPZ-fed mice were treated with vehicle or ICA at 12.5 or 25 mg/kg beginning at three weeks post CPZ feeding daily for three weeks. Their brain tissue sections were stained with oil red O, luxol-fast blue (LFB) and immunohistochemistry to characterize the levels of brain demyelination, myelin basic protein (MBP) and brain-derived neurotrophic factor (BDNF) and the numbers of oligodendrocytes (Ols), oligodendrocyte progenitor cells (OPCs), microglia and astrocytes in mice. Compared with the healthy controls, CPZ feeding caused the brain demyelination by increasing NG2+ OPCs, but decreased oil red O and LFB staining, MBP level and GST-pi+ Ols in the brain corpus callosum region of mice. Furthermore, CPZ feeding decreased the number of BDNF+ cells in the brain cortex and hippocampus regions, but increased microglia in the brain corpus callosum, cortex and caudate putamen, and astrocytes in the corpus callosum regions of mice. Treatment with ICA significantly mitigated or abrogated the toxic demyelination of CPZ by preserving MBP and BDNF proteins and modulating the numbers of Ols, OPCs, microglia and astrocytes in the brain of mice. ICA treatment significantly ameliorated the CPZ-mediated demyelination and modulated the number of Ols, microglia and astrocytes in the brain of mice.
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Affiliation(s)
- Hengri Cong
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Beijing Institute of Brain Disorders, Capital Medical University, No.119 South 4(th) Ring West Road, Fengtai District, Beijing, 100160, China
| | - Mengru Liang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing Institute of Brain Disorders, No.45 Changchun Street, Xicheng District, Beijing, 100053, China
| | - Yupeng Wang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Beijing Institute of Brain Disorders, Capital Medical University, No.119 South 4(th) Ring West Road, Fengtai District, Beijing, 100160, China
| | - Haoxiao Chang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Beijing Institute of Brain Disorders, Capital Medical University, No.119 South 4(th) Ring West Road, Fengtai District, Beijing, 100160, China; Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing Institute of Brain Disorders, No.45 Changchun Street, Xicheng District, Beijing, 100053, China
| | - Li Du
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Beijing Institute of Brain Disorders, Capital Medical University, No.119 South 4(th) Ring West Road, Fengtai District, Beijing, 100160, China
| | - Xinghu Zhang
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Beijing Institute of Brain Disorders, Capital Medical University, No.119 South 4(th) Ring West Road, Fengtai District, Beijing, 100160, China
| | - Linlin Yin
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Beijing Institute of Brain Disorders, Capital Medical University, No.119 South 4(th) Ring West Road, Fengtai District, Beijing, 100160, China; Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing Institute of Brain Disorders, No.45 Changchun Street, Xicheng District, Beijing, 100053, China.
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8
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Williams AM, Cole PD. Biomarkers of Cognitive Impairment in Pediatric Cancer Survivors. J Clin Oncol 2021; 39:1766-1774. [PMID: 33886369 DOI: 10.1200/jco.20.02436] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- AnnaLynn M Williams
- Department of Epidemiology and Cancer Control, St Jude Children's Research Hospital, Memphis, TN
| | - Peter D Cole
- Rutgers Cancer Institute of New Jersey, Robert Wood Johnson Medical School, New Brunswick, NJ
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9
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Balmik AA, Chinnathambi S. Methylation as a key regulator of Tau aggregation and neuronal health in Alzheimer's disease. Cell Commun Signal 2021; 19:51. [PMID: 33962636 PMCID: PMC8103764 DOI: 10.1186/s12964-021-00732-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/10/2021] [Indexed: 12/26/2022] Open
Abstract
Neurodegenerative diseases like Alzheimer's, Parkinson's and Huntington's disease involves abnormal aggregation and accumulation of toxic proteins aggregates. Post-translational modifications (PTMs) of the causative proteins play an important role in the etiology of disease as they could either slow down or accelerate the disease progression. Alzheimer disease is associated with the aggregation and accumulation of two major protein aggregates-intracellular neurofibrillary tangles made up of microtubule-associated protein Tau and extracellular Amyloid-β plaques. Post-translational modifications are important for the regulation of Tau`s function but an imbalance in PTMs may lead to abnormal Tau function and aggregation. Tau methylation is one of the important PTM of Tau in its physiological state. However, the methylation signature on Tau lysine changes once it acquires pathological aggregated form. Tau methylation can compete with other PTMs such as acetylation and ubiquitination. The state of PTM at these sites determines the fate of Tau protein in terms of its function and stability. The global methylation in neurons, microglia and astrocytes are involved in multiple cellular functions involving their role in epigenetic regulation of gene expression via DNA methylation. Here, we have discussed the effect of methylation on Tau function in a site-specific manner and their cross-talk with other lysine modifications. We have also elaborated the role of methylation in epigenetic aspects and neurodegenerative conditions associated with the imbalance in methylation metabolism affecting global methylation state of cells. Video abstract.
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Affiliation(s)
- Abhishek Ankur Balmik
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008,, Pune, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002,, India
| | - Subashchandrabose Chinnathambi
- Neurobiology Group, Division of Biochemical Sciences, CSIR-National Chemical Laboratory (CSIR-NCL), Dr. Homi Bhabha Road, 411008,, Pune, India.
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002,, India.
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10
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Involvements of Hyperhomocysteinemia in Neurological Disorders. Metabolites 2021; 11:metabo11010037. [PMID: 33419180 PMCID: PMC7825518 DOI: 10.3390/metabo11010037] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/27/2020] [Accepted: 01/01/2021] [Indexed: 12/14/2022] Open
Abstract
Homocysteine (HCY), a physiological amino acid formed when proteins break down, leads to a pathological condition called hyperhomocysteinemia (HHCY), when it is over a definite limit. It is well known that an increase in HCY levels in blood, can contribute to arterial damage and several cardiovascular disease, but the knowledge about the relationship between HCY and brain disorders is very poor. Recent studies demonstrated that an alteration in HCY metabolism or a deficiency in folate or vitamin B12 can cause altered methylation and/or redox potentials, that leads to a modification on calcium influx in cells, or into an accumulation in amyloid and/or tau protein involving a cascade of events that culminate in apoptosis, and, in the worst conditions, neuronal death. The present review will thus summarize how much is known about the possible role of HHCY in neurodegenerative disease.
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11
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Eating Pattern and Nutritional Risks among People with Multiple Sclerosis Following a Modified Paleolithic Diet. Nutrients 2020; 12:nu12061844. [PMID: 32575774 PMCID: PMC7353368 DOI: 10.3390/nu12061844] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/05/2020] [Accepted: 06/15/2020] [Indexed: 02/06/2023] Open
Abstract
Preliminary studies suggest that a modified Paleolithic diet may benefit symptoms of fatigue in progressive multiple sclerosis (MS). However, this diet restricts the consumption of eggs, dairy, and gluten-containing grains, which may increase the risk of micronutrient deficiencies. Therefore, we evaluated the nutritional safety of this diet among people with progressive MS. Three nonconsecutive 24-h dietary recalls were collected from (n = 19) progressive MS participants in the final months of a diet intervention study and analyzed using Nutrition Data System for Research (NDSR) software. Food group intake was calculated, and intake of micronutrients was evaluated and compared to individual recommendations using Nutrient Adequacy Ratios (NARs). Blood was drawn at baseline and the end of the study to evaluate biomarker changes. Mean intake of fruits and vegetables exceeded nine servings/day and most participants excluded food groups. The intake of all micronutrients from food were above 100% NAR except for vitamin D (29.6 ± 34.6%), choline (73.2 ± 27.2%), and calcium (60.3 ± 22.8%), and one participant (1/19) exceeded the Tolerable Upper Limit (UL) for zinc, one (1/19) for vitamin A, and 37% (7/19) exceeded the chronic disease risk reduction (CDRR) for sodium. When intake from supplements was included in the analysis, several individuals exceeded ULs for magnesium (5/19), zinc (2/19), sodium (7/19), and vitamins A (2/19), D (9/19), C (1/19), B6 (3/19), and niacin (10/19). Serum values of vitamins D, B12, K1, K2, and folate significantly increased compared to respective baseline values, while homocysteine and magnesium values were significantly lower at 12 months. Calcium and vitamin A serum levels did not change. This modified Paleolithic diet is associated with minimal nutritional risks. However, excessive intake from supplements may be of concern.
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12
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Moore JR, Hubler SL, Nelson CD, Nashold FE, Spanier JA, Hayes CE. 1,25-Dihydroxyvitamin D 3 increases the methionine cycle, CD4 + T cell DNA methylation and Helios +Foxp3 + T regulatory cells to reverse autoimmune neurodegenerative disease. J Neuroimmunol 2018; 324:100-114. [PMID: 30267995 DOI: 10.1016/j.jneuroim.2018.09.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 09/12/2018] [Accepted: 09/18/2018] [Indexed: 12/21/2022]
Abstract
We investigated how one calcitriol dose plus vitamin D3 reverses experimental autoimmune encephalomyelitis (EAE), a multiple sclerosis model. This protocol rapidly increased CD4+ T cell Ikzf2 transcripts, Helios protein, and CD4+Helios+FoxP3+ T regulatory cells. It also rapidly increased CD4+ T cell Bhmt1 transcripts, betaine:homocysteine methyltransferase-1 (BHMT1) enzyme activity, and global DNA methylation. BHMT1 transmethylates homocysteine to replenish methionine. Targeting the Vdr gene in T cells decreased Ikzf2 and Bhmt1 gene expression, reduced DNA methylation, and elevated systemic homocysteine in mice with EAE. We hypothesize that calcitriol drives a transition from encephalitogenic CD4+ T cell to Treg cell dominance by upregulating Ikzf2 and Bhmt1, recycling homocysteine to methionine, reducing homocysteine toxicity, maintaining DNA methylation, and stabilizing CD4+Helios+FoxP3+Tregulatory cells. Conserved vitamin D-responsive element (VDRE)-type sequences in the Bhmt1 and Ikzf2 promoters, the universal need for methionine in epigenetic regulation, and betaine's protective effects in MTHFR-deficiency suggest similar regulatory mechanisms exist in humans.
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Affiliation(s)
- Jerott R Moore
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | | | - Corwin D Nelson
- Department of Animal Sciences, University of Florida, Gainesville, FL 32611, United States
| | - Faye E Nashold
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States
| | - Justin A Spanier
- Rheumatic and Autoimmune Diseases, Center for Immunology, Department of Medicine, University of Minnesota, Minneapolis, MN 55455, United States.
| | - Colleen E Hayes
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, 433 Babcock Drive, Madison, WI 53706, United States.
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13
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Calabretta S, Vogel G, Yu Z, Choquet K, Darbelli L, Nicholson TB, Kleinman CL, Richard S. Loss of PRMT5 Promotes PDGFRα Degradation during Oligodendrocyte Differentiation and Myelination. Dev Cell 2018; 46:426-440.e5. [DOI: 10.1016/j.devcel.2018.06.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 04/20/2018] [Accepted: 06/27/2018] [Indexed: 12/26/2022]
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14
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Effects of single and combined metformin and L-citrulline supplementation on L-arginine-related pathways in Becker muscular dystrophy patients: possible biochemical and clinical implications. Amino Acids 2018; 50:1391-1406. [PMID: 30003335 DOI: 10.1007/s00726-018-2614-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 07/03/2018] [Indexed: 12/21/2022]
Abstract
The L-arginine/nitric oxide synthase (NOS) pathway is considered to be altered in muscular dystrophy such as Becker muscular dystrophy (BMD). We investigated two pharmacological options aimed to increase nitric oxide (NO) synthesis in 20 male BMD patients (age range 21-44 years): (1) supplementation with L-citrulline (3 × 5 g/d), the precursor of L-arginine which is the substrate of neuronal NO synthase (nNOS); and (2) treatment with the antidiabetic drug metformin (3 × 500 mg/d) which activates nNOS in human skeletal muscle. We also investigated the combined use of L-citrulline (3 × 5 g/d) and metformin (3 × 500 mg/d). Before and after treatment, we measured in serum and urine samples the concentration of amino acids and metabolites of L-arginine-related pathways and the oxidative stress biomarker malondialdehyde (MDA). Compared to healthy subjects, BMD patients have altered NOS, arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT) pathways. Metformin treatment resulted in concentration decrease of arginine and MDA in serum, and of homoarginine (hArg) and guanidinoacetate (GAA) in serum and urine. L-Citrulline supplementation resulted in considerable increase of the concentrations of amino acids and creatinine in the serum, and in their urinary excretion rates. Combined use of metformin and L-citrulline attenuated the effects obtained from their single administrations. Metformin, L-citrulline or their combination did not alter serum nitrite and nitrate concentrations and their urinary excretion rates. In conclusion, metformin or L-citrulline supplementation to BMD patients results in remarkable antidromic changes of the AGAT and GAMT pathways. In combination, metformin and L-citrulline at the doses used in the present study seem to abolish the biochemical effects of the single drugs in slight favor of L-citrulline.
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15
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Abstract
The biosynthesis of B12, involving up to 30 different enzyme-mediated steps, only occurs in bacteria. Thus, most eukaryotes require an external source of B12, and yet the vitamin appears to have only two functions in eukaryotes: as a cofactor for the enzymes methionine synthase and methylmalonylCoA mutase. These two functions are crucial for normal health in humans, and in particular, the formation of methionine is essential for providing methyl groups for over 100 methylation processes. Interference with the methionine synthase reaction not only depletes the body of methyl groups but also leads to the accumulation of homocysteine, a risk factor for many diseases. The syndrome pernicious anemia, characterized by lack of intrinsic factor, leads to a severe, sometimes fatal form of B12 deficiency. However, there is no sharp cutoff for B12 deficiency; rather, there is a continuous inverse relationship between serum B12 and a variety of undesirable outcomes, including neural tube defects, stroke, and dementia. The brain is particularly vulnerable; in children, inadequate B12 stunts brain and intellectual development. Suboptimal B12 status (serum B12<300pmol/L) is very common, occurring in 30%-60% of the population, in particular in pregnant women and in less-developed countries. Thus, many tens of millions of people in the world may suffer harm from having a poor B12 status. Public health steps are urgently needed to correct this inadequacy.
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Affiliation(s)
- A David Smith
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom.
| | - Martin J Warren
- School of Biosciences, University of Kent, Canterbury, Kent, United Kingdom
| | - Helga Refsum
- Department of Nutrition, University of Oslo, Oslo, Norway
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16
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Bystrická Z, Laubertová L, Ďurfinová M, Paduchová Z. Methionine metabolism and multiple sclerosis. Biomarkers 2017; 22:747-754. [DOI: 10.1080/1354750x.2017.1334153] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Zuzana Bystrická
- Institute of Medical Chemistry, Biochemistry, and Clinical Chemistry, Faculty of Medicine, Comenius University, Bratislava, Slovakia
| | - Lucia Laubertová
- Institute of Medical Chemistry, Biochemistry, and Clinical Chemistry, Faculty of Medicine, Comenius University, Bratislava, Slovakia
| | - Monika Ďurfinová
- Institute of Medical Chemistry, Biochemistry, and Clinical Chemistry, Faculty of Medicine, Comenius University, Bratislava, Slovakia
| | - Zuzana Paduchová
- Institute of Medical Chemistry, Biochemistry, and Clinical Chemistry, Faculty of Medicine, Comenius University, Bratislava, Slovakia
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17
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Emerging Role for Methylation in Multiple Sclerosis: Beyond DNA. Trends Mol Med 2017; 23:546-562. [PMID: 28478950 DOI: 10.1016/j.molmed.2017.04.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 03/29/2017] [Accepted: 04/10/2017] [Indexed: 12/29/2022]
Abstract
Multiple Sclerosis (MS) is a chronic inflammatory disease of the central nervous system. The inflammatory and neurodegenerative pathways driving MS are modulated by DNA, lysine, and arginine methylation, as evidenced by studies made possible by novel tools for methylation detection or loss of function. We present evidence that MS is associated with genetic variants and metabolic changes that impact on methylation. Further, we comprehensively review current understanding of how methylation can impact on central nervous system (CNS) resilience and neuroregenerative potential, as well as inflammatory versus regulatory T helper (Th) cell balance. These findings are discussed in the context of therapeutic relevance for MS, with broad implications in other neurologic and immune-mediated diseases.
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18
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Voelker P, Sheese BE, Rothbart MK, Posner MI. Methylation polymorphism influences practice effects in children during attention tasks. Cogn Neurosci 2017; 8:72-84. [PMID: 27050482 PMCID: PMC5605136 DOI: 10.1080/17588928.2016.1170006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Epigenetic mechanisms mediate the influence of experience on gene expression. Methylation is a principal method for inducing epigenetic effects on DNA. In this paper, we examine alleles of the methylenetetrahydrofolate reductase (MTHFR) gene that vary enzyme activity, altering the availability of the methyl donor and thus changing the efficiency of methylation. We hypothesized that alleles of the MTHFR gene would influence behavior in an attention-related task in conjunction with genes known to influence attention. We found that seven-year-old children homozygous for the C allele of MTHFR in interaction with the catechol O-methyltransferase (COMT) gene showed greater improvement in overall reaction time (RT) and in conflict resolution with practice on the Attention Network Test (ANT). This finding indicates that methylation may operate on or through genes that influence executive network operation. However, MTHFR T allele carriers showed faster overall RT and conflict resolution. Some children showed an initial improvement in ANT RT followed by a decline in performance, and we found that alleles of the dopamine beta-hydroxylase (DBH) gene were related to this performance decline. These results suggest a genetic dissociation between improvement while learning a skill and reduction in performance with continued practice.
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Affiliation(s)
| | - Brad E Sheese
- b Psychology , Illinois Wesleyan University , Bloomington , USA
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19
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Troesch B, Weber P, Mohajeri MH. Potential Links between Impaired One-Carbon Metabolism Due to Polymorphisms, Inadequate B-Vitamin Status, and the Development of Alzheimer's Disease. Nutrients 2016; 8:E803. [PMID: 27973419 PMCID: PMC5188458 DOI: 10.3390/nu8120803] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 12/06/2016] [Accepted: 12/07/2016] [Indexed: 12/24/2022] Open
Abstract
Alzheimer's disease (AD) is the major cause of dementia and no preventive or effective treatment has been established to date. The etiology of AD is poorly understood, but genetic and environmental factors seem to play a role in its onset and progression. In particular, factors affecting the one-carbon metabolism (OCM) are thought to be important and elevated homocysteine (Hcy) levels, indicating impaired OCM, have been associated with AD. We aimed at evaluating the role of polymorphisms of key OCM enzymes in the etiology of AD, particularly when intakes of relevant B-vitamins are inadequate. Our review indicates that a range of compensatory mechanisms exist to maintain a metabolic balance. However, these become overwhelmed if the activity of more than one enzyme is reduced due to genetic factors or insufficient folate, riboflavin, vitamin B6 and/or vitamin B12 levels. Consequences include increased Hcy levels and reduced capacity to synthetize, methylate and repair DNA, and/or modulated neurotransmission. This seems to favor the development of hallmarks of AD particularly when combined with increased oxidative stress e.g., in apolipoprotein E (ApoE) ε4 carriers. However, as these effects can be compensated at least partially by adequate intakes of B-vitamins, achieving optimal B-vitamin status for the general population should be a public health priority.
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Affiliation(s)
- Barbara Troesch
- DSM Nutritional Products Ltd., Wurmisweg 576, Kaiseraugst 4303, Switzerland.
| | - Peter Weber
- DSM Nutritional Products Ltd., Wurmisweg 576, Kaiseraugst 4303, Switzerland.
| | - M Hasan Mohajeri
- DSM Nutritional Products Ltd., Wurmisweg 576, Kaiseraugst 4303, Switzerland.
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20
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Hsu CC, Chou PT, Zare RN. Imaging of Proteins in Tissue Samples Using Nanospray Desorption Electrospray Ionization Mass Spectrometry. Anal Chem 2015; 87:11171-5. [DOI: 10.1021/acs.analchem.5b03389] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Cheng-Chih Hsu
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Pi-Tai Chou
- Department
of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Richard N. Zare
- Department
of Chemistry, Stanford University, Stanford, California 94305, United States
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21
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Li CH, Lin MH, Chu SH, Tu PH, Fang CC, Yen CH, Liang PI, Huang JC, Su YC, Sytwu HK, Chen YMA. Role of glycine N-methyltransferase in the regulation of T-cell responses in experimental autoimmune encephalomyelitis. Mol Med 2015; 20:684-96. [PMID: 25535034 DOI: 10.2119/molmed.2014.00133] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 12/12/2014] [Indexed: 01/18/2023] Open
Abstract
Glycine N-methyltransferase (GNMT) is known for its function as a tumor suppressor gene. Since 100% of female Gnmt(-/-) mice developed hepatocellular carcinoma, we hypothesized that Gnmt(-/-) mice may have defective immune surveillance. In this study, we examined the immune modulation of GNMT in T-cell responses using experimental autoimmune encephalomyelitis (EAE). The results showed that EAE severity was reduced significantly in Gnmt(-/-) mice. Pathological examination of the spinal cords revealed that Gnmt(-/-) mice had significantly lower levels of mononuclear cell infiltration and demyelination than the wild-type mice. In addition, quantitative real-time PCR showed that expression levels of proinflammatory cytokines, including interferon (IFN)-γ and interleukin (IL)-17A, were much lower in the spinal cord of Gnmt(-/-) than in that of wild-type mice. Accordingly, myelin oligodendrocyte glycoprotein (MOG)-specific T-cell proliferation and induction of T-helper (Th)1 and Th17 cells were markedly suppressed in MOG(35-55)-induced Gnmt(-/-) mice. Moreover, the number of regulatory T (Treg) cells was increased significantly in these mice. When the T-cell receptor was stimulated, the proliferative capacity and the activation status of mTOR-associated downstream signaling were decreased significantly in Gnmt(-/-) CD4(+) T cells via an IL-2- and CD25-independent manner. Moreover, GNMT deficiency enhanced the differentiation of Treg cells without affecting the differentiation of Th1 and Th17 cells. Furthermore, the severity of EAE in mice adoptive transferred with GNMT-deficient CD4(+) T cells was much milder than in those with wild-type CD4(+) T cells. In summary, our findings suggest that GNMT is involved in the pathogenesis of EAE and plays a crucial role in the regulation of CD4(+) T-cell functions.
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Affiliation(s)
- Chung-Hsien Li
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan.,Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ming-Hong Lin
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Shih-Han Chu
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan.,Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Pang-Hsien Tu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Cheng-Chieh Fang
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan.,Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chia-Hung Yen
- Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan.,Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Peir-In Liang
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Jason C Huang
- Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Yu-Chia Su
- National Laboratory Animal Center, National Applied Research Laboratories
| | - Huey-Kang Sytwu
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Yi-Ming Arthur Chen
- Department of Microbiology and Immunology, Institute of Medical Research and Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Center for Infectious Disease and Cancer Research (CICAR), Kaohsiung Medical University, Kaohsiung, Taiwan.,Institute of Biomedical Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
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22
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Cheng X. Structural and functional coordination of DNA and histone methylation. Cold Spring Harb Perspect Biol 2014; 6:6/8/a018747. [PMID: 25085914 DOI: 10.1101/cshperspect.a018747] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
One of the most fundamental questions in the control of gene expression in mammals is how epigenetic methylation patterns of DNA and histones are established, erased, and recognized. This central process in controlling gene expression includes coordinated covalent modifications of DNA and its associated histones. This article focuses on structural aspects of enzymatic activities of histone (arginine and lysine) methylation and demethylation and functional links between the methylation status of the DNA and histones. An interconnected network of methyltransferases, demethylases, and accessory proteins is responsible for changing or maintaining the modification status of specific regions of chromatin.
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Affiliation(s)
- Xiaodong Cheng
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322
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23
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Davis W, van Rensburg SJ, Cronje FJ, Whati L, Fisher LR, van der Merwe L, Geiger D, Hassan MS, Matsha T, Erasmus RT, Kotze MJ. The fat mass and obesity-associated FTO rs9939609 polymorphism is associated with elevated homocysteine levels in patients with multiple sclerosis screened for vascular risk factors. Metab Brain Dis 2014; 29:409-19. [PMID: 24532085 DOI: 10.1007/s11011-014-9486-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 01/08/2014] [Indexed: 12/20/2022]
Abstract
UNLABELLED The previously reported link between homocysteine and obesity, both identified as established risk factors for multiple sclerosis (MS), has not previously been studied in relation to the fat mass and obesity-associated (FTO) gene. AIM To investigate the mechanism underlying homocysteine accumulation in MS patients. A total of 114 patients and 195 population-matched controls were analysed for the FTO rs9939609 polymorphism. Homocysteine levels were measured in a subgroup of 60 patients and 87 controls screened for multiple vascular risk factors. After adjustment for potential confounders, the risk-associated FTO rs9939609 A-allele was associated with raised homocysteine levels (p = 0.003) in patients diagnosed with MS, but not in controls. Homocysteine levels correlated positively with body mass index (BMI) (p = 0.045) and total cholesterol levels (p = 0.048). Both homocysteine (p = 0.011) and BMI (p = 0.017) were significantly reduced with higher intake of folate in the diet. Higher BMI also correlated with increased intake of saturated/trans fat (p < 0.01) and low physical activity (p < 0.006). Daily intake of at least five fruits and vegetables had a favourable lowering effect on the Expanded Disability Status Scale (EDSS) (p = 0.035), while smoking increased MS disability (p < 0.001). This study has shown for the first time that having a diagnosis of MS moderates the effect of the FTO rs9939609 polymorphism on homocysteine levels. This is consistent with the role of FTO in demethylation and epigenetic changes. Identification of FTO rs9939609 reinforces the importance of adequate fruit, vegetable and folate and restriction of saturated/trans fat intake in the diet.
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Affiliation(s)
- Wiliam Davis
- Division of Chemical Pathology, Department of Pathology, National Health Laboratory Service (NHLS) and Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa,
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Abstract
The last one and half a decade witnessed an outstanding re-emergence of attention and remarkable progress in the field of protein methylation. In the present article, we describe the early discoveries in research and review the role protein methylation played in the biological function of the antiproliferative gene, BTG2/TIS21/PC3.
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Affiliation(s)
- Woon Ki Paik
- Professor Emeritus, Temple University School of Medicine, Philadelphia, PA, USA
| | - Sangduk Kim
- Professor Emeritus, Temple University School of Medicine, Philadelphia, PA, USA
| | - In Kyoung Lim
- Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, Suwon, Korea
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25
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Esse R, Imbard A, Florindo C, Gupta S, Quinlivan EP, Davids M, Teerlink T, Tavares de Almeida I, Kruger WD, Blom HJ, Castro R. Protein arginine hypomethylation in a mouse model of cystathionine β-synthase deficiency. FASEB J 2014; 28:2686-95. [PMID: 24532665 DOI: 10.1096/fj.13-246579] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Accumulation of the homocysteine (Hcy) precursor S-adenosylhomocysteine (AdoHcy) may cause cellular hypomethylation in the setting of hyperhomocysteinemia because of cystathionine β-synthase (CBS) deficiency, an inborn error of metabolism. To test this hypothesis, DNA and protein arginine methylation status were assessed in liver, brain, heart, and kidney obtained from a previously described mouse model of CBS deficiency. Metabolite levels in tissues and serum were determined by high-performance liquid chromatography or liquid chromatography-electrospray ionization-tandem mass spectrometry. Global DNA and protein arginine methylation status were evaluated as the contents of 5-methyldeoxycytidine in DNA and of methylarginines in proteins, respectively. In addition, histone arginine methylation was assessed by Western blotting. CBS-deficient mice exhibited increased (>6-fold) Hcy and AdoHcy levels in all tissues examined compared with control levels. In addition, global DNA methylation status was not affected, but global protein arginine methylation status was decreased (10-35%) in liver and brain. Moreover, asymmetric dimethylation of arginine 3 on histone H4 (H4R3me2a) content was markedly decreased in liver, and no differences were observed for the other histone arginine methylation marks examined. Our results show that CBS-deficient mice present severe accumulation of tissue Hcy and AdoHcy, protein arginine hypomethylation in liver and brain, and decreased H4R3me2a content in liver. Therefore, protein arginine hypomethylation arises as a potential player in the pathophysiology of CBS deficiency.
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Affiliation(s)
- Ruben Esse
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands; Institute for Medicines and Pharmaceutical Sciences (iMed.UL) and
| | - Apolline Imbard
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands; Service de Biochimie-Hormonologie, Hôpital Robert Debré, Assistance Publique-Hôpitaux de Paris (APHP), Paris, France
| | | | - Sapna Gupta
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
| | - Eoin P Quinlivan
- Biomedical Mass Spectrometry Laboratory, University of Florida, Gainesville, Florida, USA; and
| | - Mariska Davids
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands
| | - Tom Teerlink
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands
| | - Isabel Tavares de Almeida
- Institute for Medicines and Pharmaceutical Sciences (iMed.UL) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | - Warren D Kruger
- Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
| | - Henk J Blom
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands; Laboratory for Clinical Biochemistry and Metabolism, Department of General Pediatrics, Center for Pediatrics and Adolescent Medicine, University Hospital, Freiburg, Germany
| | - Rita Castro
- Institute for Medicines and Pharmaceutical Sciences (iMed.UL) and Department of Biochemistry and Human Biology, Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
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26
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Moghaddasi M, Mamarabadi M, Mohebi N, Razjouyan H, Aghaei M. Homocysteine, vitamin B12 and folate levels in Iranian patients with Multiple Sclerosis: a case control study. Clin Neurol Neurosurg 2013; 115:1802-5. [PMID: 23756083 DOI: 10.1016/j.clineuro.2013.05.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 02/19/2013] [Accepted: 05/02/2013] [Indexed: 11/17/2022]
Abstract
BACKGROUND Recently, homocysteine (Hcy), folate, and vitamin B12 have been proposed to have several roles on MS pathogenesis. OBJECTIVE We performed this study to determine the role of serum levels of Hcy, vitamin B12, and folate in patients with relapsing remitting MS (RRMS) and compared them with healthy controls. METHODS We recruited 75 RRMS patients and 75 subjects as controls with the same age and sex. Homocysteine was measured using fluorimetric high-performance liquid chromatography. Plasma folate and vitamin B12 levels were measured through ion-capture method. RESULTS Mean plasma levels of vitamin B12, folate, and Hcy in cases were 342.64 ± 210.66 pg/ml, 9.74 ± 4.77 ng/ml, and 22.73 ± 11.63 μM/L, respectively, which showed significant difference in comparison with the controls. In addition, there were significant correlations between mean serum Hcy levels and duration of disease (r=0.2, p=0.05) and treatment with interferon (r=0.21, p=0.01). In cases, Hcy level was higher among those on β interferon (24.56 ± 11.87 vs. 19.71 ± 10.75, p=0.01). CONCLUSIONS We concluded that serum levels of vitamin B12 and folate decreased in RRMS patients, but Hcy levels increased significantly. It seems necessary to conduct prospective trials to determine whether the treatment with supplements and correct biomarker levels in the early stage of the disease can change the course of the disease. We recommend regular checking of the serum level of Hcy in patients who use disease-modifying drugs.
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Affiliation(s)
- Mehdi Moghaddasi
- Department of Neurology, Rasool Akram Hospital, Tehran University of Medical Sciences, Tehran, Iran
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Zoccolella S, Tortorella C, Iaffaldano P, Direnzo V, D'Onghia M, Paolicelli D, Livrea P, Trojano M. Elevated plasma homocysteine levels in patients with multiple sclerosis are associated with male gender. J Neurol 2012; 259:2105-10. [PMID: 22421956 DOI: 10.1007/s00415-012-6464-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 02/16/2012] [Accepted: 02/17/2012] [Indexed: 01/21/2023]
Abstract
Elevated homocysteine (Hcy) levels exert several neurotoxic actions and vascular dysfunctions that may be involved in pathogenesis and progression of multiple sclerosis (MS). The effective role of Hcy in MS however remains to be determined. The aim of this work was to compare plasma Hcy levels in MS patients and neurological disease controls (NDC) and to evaluate their relationships with clinical and demographic variables. In this cross-sectional study, we examined plasma Hcy levels in 217 patients with MS [53 clinically isolated syndromes (CIS) suggestive of MS, 134 relapsing remitting (RR), 23 secondary progressive (SP) and seven primary progressive (PP) MS], recruited among patients attending a tertiary clinical center in southern Italy and in 219 age/sex-matched controls. Median Hcy levels were slightly higher in MS patients compared to NDC (9.1 μmol/l; range, 3.4-35.9 vs. 8.6, range 3.5-27.4; p = 0.02). Median Hcy concentrations were increased in males more than in females in the MS population (10.4 vs. 8.4; p < 0.0001), whereas no differences across genders were found in NDC (9.1 vs. 8.5). Hcy levels were higher in male MS patients compared to the male NDC patients (p = 0.001). Patients with CIS had lower Hcy (7.5 μmol/l; p = 0.004) compared to patients with RR (9.5 μmol/l), SP (10.1 μmol/l) and PP (9.9 μmol/l). Median Hcy concentration was higher in patients with disease duration longer than 22 months (9.7 vs. 8.6 μmol/l; p = 0.02). Plasma Hcy levels are increased in patients with definite MS. Higher Hcy levels are associated with male sex, suggesting a role of Hcy in neurodegenerative processes of MS, which are prominent in male patients.
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Affiliation(s)
- Stefano Zoccolella
- Department of Neurosciences and Organs of Senses, University of Bari, Ospedale Policlinico, P.zza G. Cesare 11, 70124, Bari, Italy
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Kitade I, Hoso M, Matsuzaki T, Yoshida S, Kamijyo A, Araki Y, Takahashi I. Histopathological Changes in Surrounding Tissue of the Sciatic Nerve after Spinal Cord Injury in Rats. J Phys Ther Sci 2012. [DOI: 10.1589/jpts.24.817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Ippei Kitade
- Division of Rehabilitation Medicine, University of Fukui Hospital
| | - Masahiro Hoso
- Division of Health Sciences, Kanazawa University Graduate School of Medical Science
| | - Taro Matsuzaki
- Division of Health Sciences, Kanazawa University Graduate School of Medical Science
| | - Shinya Yoshida
- Department of Rehabilitation Medicine, Kanazawa University Hospital
| | - Akio Kamijyo
- Department of Rehabilitation Medicine, Azumino Red Cross Hospital
| | - Yoshitaka Araki
- Department of Rehabilitation Medicine, Kanazawa Cranial Nerve Surgery Hospital
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Zhu Y, He ZY, Liu HN. Meta-analysis of the relationship between homocysteine, vitamin B12, folate, and multiple sclerosis. J Clin Neurosci 2011; 18:933-8. [DOI: 10.1016/j.jocn.2010.12.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 11/16/2010] [Accepted: 12/09/2010] [Indexed: 10/18/2022]
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Bidwell GL, Whittom AA, Thomas E, Lyons D, Hebert MD, Raucher D. A thermally targeted peptide inhibitor of symmetrical dimethylation inhibits cancer-cell proliferation. Peptides 2010; 31:834-41. [PMID: 20167239 PMCID: PMC2872552 DOI: 10.1016/j.peptides.2010.02.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Revised: 02/09/2010] [Accepted: 02/09/2010] [Indexed: 01/29/2023]
Abstract
Targeting splicing machinery components is an underdeveloped strategy for cancer therapy. Uridine-rich small nuclear ribonucleoproteins (UsnRNPs) are essential spliceosome components that recognize splice sites in newly transcribed RNA. The major spliceosomal snRNPs are comprised of UsnRNA bound by a ring of Sm proteins. The survival of motor neuron (SMN) complex provides specificity for binding of Sm proteins to UsnRNAs. Three of the seven proteins that comprise the Sm core possess post-translationally modified C-terminal symmetric dimethylarginine (sDMA) residues which promote binding of these proteins to SMN. Here we describe a peptide inhibitor of sDMA that is capable of interfering with SMN/SmB interaction. The inhibitory peptide was attached to elastin-like polypeptide, a thermally responsive macromolecular carrier, in order to increase its stability and allow enhancement of its cellular uptake by thermal targeting. The fusion polypeptide inhibited the interaction of SMN/SmB, inhibited proliferation, and induced apoptosis in HeLa cells.
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Affiliation(s)
- Gene L. Bidwell
- Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA
| | - Angela A. Whittom
- Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA
| | - Emily Thomas
- Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA
| | - Daniel Lyons
- Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA
| | - Michael D. Hebert
- Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA
| | - Drazen Raucher
- Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA
- Corresponding Author. Department of Biochemistry. University of Mississippi Medical Center. 2500 North State Street, Jackson, MS 39216. USA. Phone: 601-984-1510. Fax: 601-984-1501.
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Snijders APL, Hung ML, Wilson SA, Dickman MJ. Analysis of arginine and lysine methylation utilizing peptide separations at neutral pH and electron transfer dissociation mass spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2010; 21:88-96. [PMID: 19850496 DOI: 10.1016/j.jasms.2009.09.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Revised: 09/11/2009] [Accepted: 09/11/2009] [Indexed: 05/28/2023]
Abstract
Arginine and lysine methylation are widespread protein post-translational modifications. Peptides containing these modifications are difficult to retain using traditional reversed-phase liquid chromatography because they are intrinsically basic/hydrophilic and often fragment poorly during collision induced fragmentation (CID). Therefore, they are difficult to analyze using standard proteomic workflows. To overcome these caveats, we performed peptide separations at neutral pH, resulting in increased retention of the hydrophilic/basic methylated peptides before identification using MS/MS. Alternatively trifluoroacetic acid (TFA) was used for increased trapping of methylated peptides. Electron-transfer dissociation (ETD) mass spectrometry was then used to identify and characterize methylated residues. In contrast to previous reports utilizing ETD for arginine methylation, we observed significant amount of side-chain fragmentation. Using heavy methyl stable isotope labeling with amino acids in cell culture it was shown that, similar to CID, a loss of monomethylamine or dimethylamine from the arginine methylated side-chain during ETD can be used as a diagnostic to determine the type of arginine methylation. CID of lysine methylated peptides does not lead to significant neutral losses, but ETD is still beneficial because of the high charge states of such peptides. The developed LC MS/MS methods were successfully applied to tryptic digests of a number of methylated proteins, including splicing factor proline-glutamine-rich protein (SFPQ), RNA and export factor-binding protein 2 (REF2-I) and Sul7D, demonstrating significant advantages over traditional LC MS/MS approaches.
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Affiliation(s)
- Ambrosius P L Snijders
- Biological and Environmental Systems, Department of Chemical and Process Engineering, University of Sheffield, Sheffield, United Kingdom
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Barić I. Inherited disorders in the conversion of methionine to homocysteine. J Inherit Metab Dis 2009; 32:459-71. [PMID: 19585268 DOI: 10.1007/s10545-009-1146-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 04/20/2009] [Accepted: 05/05/2009] [Indexed: 12/15/2022]
Abstract
During the last decade much important new information relating to the metabolic pathway from methionine to homocysteine has been gained. Interest has been stimulated by the discovery of two novel disorders, glycine N-methyltransferase deficiency and S-adenosylhomocysteine hydrolase deficiency. Another disorder in this pathway, methionine adenosyltransferase deficiency, has been increasingly detected, thanks to the expansion of newborn screening programmes by tandem mass spectrometry technology. These significant steps allow important insight into the pathogenesis of these three disorders, as well as into the mechanisms of damage to various organs (liver, brain, muscle) and point to the relevance of these disorders for crucial biological processes such as methylation, transsulfuration or carcinogenesis in mammals, the pathogenesis of numerous pathological conditions, in particular those associated with hyperhomocysteinaemia, the action and possible toxicity of some drugs or consequences of nutritional variations. This review summarizes current knowledge of three inherited disorders in this metabolic pathway and draws attention to their much broader significance for human health and understanding of important biological processes.
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Affiliation(s)
- Ivo Barić
- Department of Pediatrics, University Hospital Center and School of Medicine, Zagreb, Croatia.
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Post-translational Modifications of Chicken Myelin Basic Protein Charge Components. Neurochem Res 2008; 34:360-72. [DOI: 10.1007/s11064-008-9788-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Accepted: 06/17/2008] [Indexed: 11/27/2022]
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Mastronardi FG, Tsui H, Winer S, Wood DD, Selvanantham T, Galligan C, Fish EN, Dosch HM, Moscarello MA. Synergy between paclitaxel plus an exogenous methyl donor in the suppression of murine demyelinating diseases. Mult Scler 2007; 13:596-609. [PMID: 17548438 DOI: 10.1177/1352458506072167] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Progressive demyelination in multiple sclerosis (MS) reflects the negative balance between myelin damage and repair due to physical and molecular barriers, such as astrocytic glial scars, between oligodendrocytes and target neurons. In this paper, we show that combination therapy with paclitaxel (Taxol) plus the universal methyl-donor, vitamin B12CN (B12CN), dramatically limits progressive demyelination, and enhances remyelination in several independent, immune and nonimmune, in vivo and in vitro model systems. Combination therapy significantly reduced clinical signs of EAE in SJL mice, as well as the spontaneously demyelinating ND4 transgenic mouse. Astrocytosis was normalised in parallel to ultrastructural and biochemical evidence of remyelination. The combination therapy suppressed T cell expansion, reduced IFN-gamma, while enhancing IFN-beta and STAT-1 expression, STAT-1 phosphorylation and methylation of STAT-1 and MBP in the brain. Paclitaxel/B12CN has nearly identical effects to the previously described combination of IFN-beta/ B12CN, whose clinical usefulness is transient because of IFN-neutralising antibodies, not observed (or expected) with the present drug combination. This report provides a mechanistic foundation for the development of a new therapeutic strategy in humans with MS.
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Affiliation(s)
- F G Mastronardi
- Department of Structural Biology and Biochemistry, The Hospital for Sick Children, University Health Network, Toronto, Ontario, Canada.
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Abstract
Although the field of protein methylation enjoys widespread interest in the scientific literature of today, this is a recent phenomenon. Papers on 'protein methylation' were first published in the 1960s. By the early 1980s, it was known that lysine, arginine, histidine and dicarboxylic amino acids were post-translationally methylated by highly specific methyltransferases. However, despite these early advances, the biological importance of these reactions remained largely unproven. With the introduction of modern molecular biology techniques in the mid-1990s, an enormous surge of interest in protein methylation occurred. It is now clear that protein methylation carries many important biological functions, including gene regulation and signal transduction. Thus, the story of protein-methylation research is a testament to both modern molecular biology and the importance of continuing to pursue lines of research in which the precise biological function might not be currently known.
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Affiliation(s)
- Woon Ki Paik
- Graduate School of Biomedical Sciences, Korea University Medical School, Seoul 136-705, Korea
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Blomster H, Puustjärvi T, Kontkanen M, Valtonen P, Teräsvirta M, Uusitalo H. Asymmetric dimethylarginine is not elevated in exfoliation syndrome but symmetric dimethylarginine is related to exfoliative glaucoma. Graefes Arch Clin Exp Ophthalmol 2006; 245:204-9. [PMID: 17024436 DOI: 10.1007/s00417-006-0425-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2006] [Revised: 06/20/2006] [Accepted: 07/18/2006] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Hyperhomocysteinemia (HH), oxidative stress and endothelial dysfunction are all implicated as possible pathogenetic factors in exfoliation syndrome (XFS) and exfoliative glaucoma (XFG). Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide and plasma level of ADMA is often elevated in HH. Thus the present study was undertaken to study plasma levels of ADMA with concomitant measurement of symmetric dimethylarginine (SDMA) and L-arginine (L-Arg) in XFS and XFG. METHODS This cross-sectional, prospective study involved 36 XFS patients, 11 of them having XFG, and 36 age- and gender-matched controls. Fasting plasma ADMA, SDMA and L-Arg levels of participants were determined. A special view was created how plasma L-Arg, ADMA and SDMA correlate to plasma homocysteine (P-Hcy). In addition, the influence of P-Hey values derived from our previous study on the above mentioned parameters were evaluated by cut-off values of P-Hcy, 12 micromol/l for women and 14.5 micromol/l for men. RESULTS The mean plasma ADMA, SDMA and L-Arg levels were 0.41, 0.49 and 62.9 micromol/l in the XFS/XFG group, and 0.41, 0.44 and 69.7 micromol/l in the control group, respectively. As all parameters within the XFS and control group were compared, no statistical significance was stated. On the other hand, a positive correlation was observed between plasma SDMA and P-Hcy in XFGs (P = 0.002), and additionally, also a statistically significant difference was in plasma SDMA between the two groups sorted by cut-off levels of P-Hcy 0.49 +/- 0.15 vs. 0.36 +/- 0.04 micromol/l, above and below cut-off levels, respectively (P = 0.001), but not between ADMA in a respective assay. The mean values of L-Arg were 64.6 +/- 17.2 vs. 74.8 +/- 13.3 microg/l, respectively (P = 0.031). In the XFS subgroup, on the contrary, there was no positive correlation between P-Hcy and plasma SDMA. CONCLUSIONS A positive correlation of plasma SDMA in respect to P-Hcy in XFGs and increase of SDMA in mild or intermediate hyperhomocysteinemia may indicate SDMA as a marker of developing XFG in hyperhomocysteinemic
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Affiliation(s)
- Hillevi Blomster
- Eye Policlinic, Institution of Deacony, Sibeliuksenkatu 6 C, 15110 Lahti, Finland.
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Ramsaransing GSM, Fokkema MR, Teelken A, Arutjunyan AV, Koch M, De Keyser J. Plasma homocysteine levels in multiple sclerosis. J Neurol Neurosurg Psychiatry 2006; 77:189-92. [PMID: 16421120 PMCID: PMC2077571 DOI: 10.1136/jnnp.2005.072199] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND There is evidence that homocysteine contributes to various neurodegenerative disorders, and elevated plasma homocysteine levels have been observed in patients with multiple sclerosis (MS). OBJECTIVE To investigate if and why plasma homocysteine levels are increased in MS, and whether they play a role in the disease course. METHODS We compared plasma levels of homocysteine in 88 patients with MS and 57 healthy controls. In the MS group, 28 had a benign course, 37 were secondary progressive, and 23 primary progressive. To explore the underlying mechanisms, we measured serum levels of vitamins B6 and B12, folate, interleukin (IL)-12, tumour necrosis factor (TNF)-alpha, leukocyte nitric oxide production, and plasma diene conjugate levels (measure of oxidative stress). RESULTS Mean (SD) plasma homocysteine concentration was higher in patients (13.8 (4.9) micromol/l) than in controls (10.1 (2.5) micromol/l; p<0.0001). However, there were no significant differences in homocysteine levels between the three clinical subgroups of MS. Serum concentrations of vitamin B6, vitamin B12, and folate were not different between patients with MS and controls. In the MS group, there were no correlations between plasma homocysteine levels and the serum concentrations of IL-12 or TNF-alpha, leukocyte nitric oxide production, or plasma diene conjugate levels. CONCLUSIONS Elevated plasma homocysteine occurs in both benign and progressive disease courses of MS, and seems unrelated to immune activation, oxidative stress, or a deficiency in vitamin B6, vitamin B12, or folate.
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Affiliation(s)
- G S M Ramsaransing
- Department of Neurology, University Medical Center Groningen, Hanzeplein 1, 9713 GZ Groningen, Netherlands
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Zhang X, Cheng X. 4 Structure of protein arginine methyltransferases. PROTEIN METHYLTRANSFERASES 2006; 24:105-21. [DOI: 10.1016/s1874-6047(06)80006-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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3 Diverse roles of protein arginine methyltransferases. PROTEIN METHYLTRANSFERASES 2006; 24:51-103. [DOI: 10.1016/s1874-6047(06)80005-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Cheng X, Collins RE, Zhang X. Structural and sequence motifs of protein (histone) methylation enzymes. ACTA ACUST UNITED AC 2005; 34:267-94. [PMID: 15869391 PMCID: PMC2733851 DOI: 10.1146/annurev.biophys.34.040204.144452] [Citation(s) in RCA: 257] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
With genome sequencing nearing completion for the model organisms used in biomedical research, there is a rapidly growing appreciation that proteomics, the study of covalent modification to proteins, and transcriptional regulation will likely dominate the research headlines in the next decade. Protein methylation plays a central role in both of these fields, as several different residues (Arg, Lys, Gln) are methylated in cells and methylation plays a central role in the "histone code" that regulates chromatin structure and impacts transcription. In some cases, a single lysine can be mono-, di-, or trimethylated, with different functional consequences for each of the three forms. This review describes structural aspects of methylation of histone lysine residues by two enzyme families with entirely different structural scaffolding (the SET proteins and Dot1p) and methylation of protein arginine residues by PRMTs.
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Affiliation(s)
- Xiaodong Cheng
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
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Mastronardi FG, Moscarello MA. Molecules affecting myelin stability: a novel hypothesis regarding the pathogenesis of multiple sclerosis. J Neurosci Res 2005; 80:301-8. [PMID: 15704220 DOI: 10.1002/jnr.20420] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In this Mini-Review we present a new hypothesis in support of the neurodegenerative theory as a mechanism for the pathogenesis of multiple sclerosis (MS). The pathogenesis of MS results from changes in two distinct CNS compartments. These are the "myelin" and "nonmyelin" compartments. The myelin compartment is where primary demyelination, amidst attempts at remyelination, is superseded in the CNS by ongoing disease. Recent evidence obtained via magnetic resonance imaging and spectroscopy techniques supports the view that the normal-appearing white matter (NAWM) in the MS brain is altered. Several biochemical changes in NAWM have been determined. These include the cationicity of myelin basic protein (MBP) as a result of the action of peptidyl argininedeiminase (PAD) activity converting arginyl residues to citrulline. The accompanying loss of positive charge makes myelin susceptible to vesiculation and MBP more susceptible to proteolytic activity. An increase of MBP autocatalysis in the MS brain might also contribute to the generation of immunodominant epitopes. Accompanying the destruction of myelin in the myelin compartment is the activation of astrocytes and microglia. These contribute to the inflammatory response and T-cell activation leading to autoimmunity. The complex environment that exists in the demyelinating brain also affects the "nonmyelin" compartment. The inappropriate up-regulation of molecules, including those of the Jagged-1-Notch-1 signal transduction pathway, affects oligodendrocyte precursor cell (OPC) differentiation. Other effectors of oligodendrocyte maturation include stathmin, a microtubule-destabilizing protein, which prevents healing in the demyelinating brain. The hypothesis we present suggests a therapeutic strategy that should 1) target the effectors within the myelin compartment and 2) enable resident OPC maturation in the nonmyelin compartment, allowing for effective repair of myelin loss. The net effect of this new therapeutic strategy is the modification of the disease environment and the stimulation of healing and repair.
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Affiliation(s)
- Fabrizio G Mastronardi
- Structural Biochemistry and Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.
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Jiang W, Roemer ME, Newsham IF. The tumor suppressor DAL-1/4.1B modulates protein arginine N-methyltransferase 5 activity in a substrate-specific manner. Biochem Biophys Res Commun 2005; 329:522-30. [PMID: 15737618 DOI: 10.1016/j.bbrc.2005.01.153] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Indexed: 11/18/2022]
Abstract
We previously identified DAL-1/4.1B as a growth suppression protein involved in the pathogenesis of lung, breast, and meningioma tumors. Using yeast two-hybrid interaction cloning, protein arginine N-methyltransferase 3 (PRMT3) was originally identified as a DAL-1/4.1B-interacting protein. PRMTs catalyze the sequential transfer of methyl groups from S-adeonsyl-l-methionine to the guanidino nitrogens of arginine residues in proteins, the effect of which can include regulation of signal transduction, transcription regulation, and RNA transport, suggesting that modulating this event may have far-reaching impact. In this study, we assessed the impact of DAL-1/4.1B binding on the activity of another family member, PRMT5, both in vitro and in cells. In contrast to PRMT3, DAL-1/4.1B was found to mediate PRMT5 by either inhibiting (Sm proteins) or enhancing (myelin basic protein) protein methylation. We propose that this interaction between a tumor suppressor and a post-translational methylation enzyme is of biological importance in controlling tumorigenesis.
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Affiliation(s)
- Wei Jiang
- David and Doreen Hermelin Laboratory of Molecular Oncogenetics, Department of Neurosurgery, Hermelin Brain Tumor Center, Henry Ford Hospital, Detroit, MI 48202, USA
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Barić I, Cuk M, Fumić K, Vugrek O, Allen RH, Glenn B, Maradin M, Pazanin L, Pogribny I, Rados M, Sarnavka V, Schulze A, Stabler S, Wagner C, Zeisel SH, Mudd SH. S-Adenosylhomocysteine hydrolase deficiency: a second patient, the younger brother of the index patient, and outcomes during therapy. J Inherit Metab Dis 2005; 28:885-902. [PMID: 16435181 PMCID: PMC2441944 DOI: 10.1007/s10545-005-0192-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Accepted: 09/02/2005] [Indexed: 10/25/2022]
Abstract
S-Adenosylhomocysteine (AdoHcy) hydrolase deficiency has been proven in a human only once, in a recently described Croatian boy. Here we report the clinical course and biochemical abnormalities of the younger brother of this proband. This younger brother has the same two mutations in the gene encoding AdoHcy hydrolase, and has been monitored since birth. We report, as well, outcomes during therapy for both patients. The information obtained suggests that the disease starts in utero and is characterized primarily by neuromuscular symptomatology (hypotonia, sluggishness, psychomotor delay, absent tendon reflexes, delayed myelination). The laboratory abnormalities are markedly increased creatine kinase and elevated aminotransferases, as well as specific amino acid aberrations that pinpoint the aetiology. The latter include, most importantly, markedly elevated plasma AdoHcy. Plasma S-adenosylmethionine (AdoMet) is also elevated, as is methionine (although the hypermethioninaemia may be absent or nonsignificant in the first weeks of life). The disease seems to be at least to some extent treatable, as shown by improved myelination and psychomotor development during dietary methionine restriction and supplementation with creatine and phosphatidylcholine.
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Affiliation(s)
- I Barić
- Department of Pediatrics, University Hospital Center and School of Medicine, Zagreb, Croatia.
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Mastronardi FG, Min W, Wang H, Winer S, Dosch M, Boggs JM, Moscarello MA. Attenuation of Experimental Autoimmune Encephalomyelitis and Nonimmune Demyelination by IFN-β plus Vitamin B12: Treatment to Modify Notch-1/Sonic Hedgehog Balance. THE JOURNAL OF IMMUNOLOGY 2004; 172:6418-26. [PMID: 15128833 DOI: 10.4049/jimmunol.172.10.6418] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Interferon-beta is a mainstay therapy of demyelinating diseases, but its effects are incomplete in human multiple sclerosis and several of its animal models. In this study, we demonstrate dramatic improvements of clinical, histological, and laboratory parameters in in vivo mouse models of demyelinating disease through combination therapy with IFN-beta plus vitamin B(12) cyanocobalamin (B(12)CN) in nonautoimmune primary demyelinating ND4 (DM20) transgenics, and in acute and chronic experimental autoimmune encephalomyelitis in SJL mice. Clinical improvement (p values <0.0001) was paralleled by near normal motor function, reduced astrocytosis, and reduced demyelination. IFN-beta plus B(12)CN enhanced in vivo and in vitro oligodendrocyte maturation. In vivo and in vitro altered expression patterns of reduced Notch-1 and enhanced expression of sonic hedgehog and its receptor were consistent with oligodendrocyte maturation and remyelination. IFN-beta-B(12)CN combination therapy may be promising for the treatment of multiple sclerosis.
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MESH Headings
- Acute Disease
- Animals
- Brain/drug effects
- Brain/metabolism
- Cell Line
- Chronic Disease
- Demyelinating Diseases/genetics
- Demyelinating Diseases/metabolism
- Demyelinating Diseases/prevention & control
- Drug Synergism
- Drug Therapy, Combination
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/metabolism
- Encephalomyelitis, Autoimmune, Experimental/prevention & control
- Female
- Hedgehog Proteins
- Humans
- Interferon-beta/therapeutic use
- Mice
- Mice, Inbred Strains
- Mice, Transgenic
- Oligodendroglia/cytology
- Oligodendroglia/drug effects
- Oligodendroglia/metabolism
- Peptide Fragments/biosynthesis
- Receptor, Notch1
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/metabolism
- Stem Cells/drug effects
- Stem Cells/metabolism
- Trans-Activators/biosynthesis
- Trans-Activators/genetics
- Trans-Activators/metabolism
- Transcription Factors
- Vitamin B 12/therapeutic use
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Affiliation(s)
- Fabrizio G Mastronardi
- Department of Structural Biology and Biochemistry, Hospital for Sick Children, Toronto, Ontario, Canada
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Kim JK, Mastronardi FG, Wood DD, Lubman DM, Zand R, Moscarello MA. Multiple sclerosis: an important role for post-translational modifications of myelin basic protein in pathogenesis. Mol Cell Proteomics 2003; 2:453-62. [PMID: 12832457 DOI: 10.1074/mcp.m200050-mcp200] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Myelin basic protein (MBP) represents a candidate autoantigen in multiple sclerosis (MS). We isolated MBP from normal and MS human white matter and purified six components (charge isomers) to compare the post-translational modifications on each. The sites and extent of methylation, deimination, and phosphorylation were documented for all tryptic peptides by mass spectrometry. We found that mono and dimethylated arginine 107 was increased in MS samples; deimination of arginine occurred at a number of sites and was elevated in MS; phosphorylation was observed in 10 peptides in normal samples but was greatly reduced or absent in most peptides from MS samples. Data obtained with MBP isolated from fresh brain obtained from a spontaneously demyelinating mouse model supported the view that the changes observed in human brain were probably related to pathogenesis of demyelination, i.e. we found decreased phosphorylation and decreased amounts of glycogen synthesis kinase in brain homogenates using specific antibodies. This study represents the first to define post-translational modifications in demyelinating disease and suggest an important role in pathogenesis.
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Affiliation(s)
- J K Kim
- Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
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48
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Abstract
Posttranslational modifications of proteins often perform a key role in the biological functioning of proteins. Some of these modifications also change the immunogenicity of proteins and peptides and create 'self'-antigens which might induce autoimmune responses. In particular modifications of arginines within a defined protein context can lead to a specific B-cell immune response. This review discusses the generation of such modifications and their relevance for autoimmunity.
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Affiliation(s)
- M A M van Boekel
- Department of Biochemistry, University of Nijmegen, Nijmegen, The Netherlands.
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Wood DD, She YM, Freer AD, Harauz G, Moscarello MA. Primary structure of equine myelin basic protein by mass spectrometry. Arch Biochem Biophys 2002; 405:137-46. [PMID: 12176067 DOI: 10.1016/s0003-9861(02)00340-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Equine myelin basic protein (MBP) has been isolated from spinal cord and shown to consist of a number of components (charge isomers) by alkaline-urea gel electrophoresis. Mass analyses of several of these components showed that each was posttranslationally modified and some have been identified. Component 1, the most cationic charge isomer, was sequenced by a combination of liquid chromatography and mass spectrometry of peptides obtained by proteolytic digestion. At 172 residues it is slightly larger than the bovine (169) and the human (170). A major difference between bovine and equine sequences was the replacement of AQGH (bovine residues 76-79) by SRDG (equine). A number of other replacements involving single amino acids were also found. Methylated arginine (residue 108 equine) was found as both the mono- and the dimethylated derivative and represents the first MS/MS evidence for this modification in any MBP.
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Affiliation(s)
- D D Wood
- Structural Biology and Biochemistry, The Hospital for Sick Children, Ont., M5G 1X8, Toronto, Canada
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50
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Rho J, Choi S, Seong YR, Cho WK, Kim SH, Im DS. Prmt5, which forms distinct homo-oligomers, is a member of the protein-arginine methyltransferase family. J Biol Chem 2001; 276:11393-401. [PMID: 11152681 DOI: 10.1074/jbc.m008660200] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We found that JBP1, known as a human homolog (Skb1Hs) of Skb1 of fission yeast, interacts with NS3 of the hepatitis C virus in a yeast two-hybrid screen. Amino acid sequence analysis revealed that Skb1Hs/JBP1 contains conserved motifs of S-adenosyl-l-methionine-dependent protein-arginine methyltransferases (PRMTs). Here, we demonstrate that Skb1Hs/JBP1, named PRMT5, is a distinct member of the PRMT family. Recombinant PRMT5 protein purified from human cells methylated myelin basic protein, histone, and the amino terminus of fibrillarin fused to glutathione S-transferase. Myelin basic protein methylated by PRMT5 contained monomethylated and dimethylated arginine residues. Recombinant glutathione S-transferase-PRMT5 protein expressed in Escherichia coli also contained the catalytic activity. Sedimentation analysis of purified PRMT5 on a sucrose density gradient indicated that PRMT5 formed distinct homo-oligomeric complexes, including a dimer and tetramer, that comigrated with the enzyme activity. The PRMT5 homo-oligomers were dissociated into a monomer in the presence of a reducing agent, whereas a monomer, dimer, and multimer were detected in the absence or at low concentrations of a reducing agent. The results indicate that both covalent linkage by a disulfide bond and noncovalent association are involved in the formation of PRMT5 homo-oligomers. Western blot analysis of sedimentation fractions suggests that endogenous PRMT5 is present as a homo-oligomer in a 293T cell extract. PRMT5 appears to have lower specific enzyme activity than PRMT1. Although PRMT1 is known to be mainly located in the nucleus, human PRMT5 is predominantly localized in the cytoplasm.
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Affiliation(s)
- J Rho
- Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Yusong, Taejeon 305-333, Republic of Korea
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